unless they are also dry and brittle, it's a pest.
hopefully it's something that took a bite, decided it didn't like it, and moved on.
i've got some holes / slats in a few leaves.. tend to be lower leaves about to be shed.. they get a little dryer than the rest (i think) and those form). this would be a lower leaf being shed, not a top / healthy leaf, though.
anythng drop on it recently? another option to consider.
keep eye on it.. if it doesn't spread, all is well.